树莓派上USB摄像头无法被OpenCV识别的问题求助

我无法让OpenCV检测到我的USB摄像头。系统似乎可以识别它，使用其他工具甚至可以拍照，但OpenCV无法正常工作。

系统识别USB设备情况 #

当我列出USB设备时，执行命令：

lsusb

输出结果：

Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 006: ID 258a:002a SINO WEALTH Gaming KB 
Bus 001 Device 005: ID 18f8:0f97 [Maxxter] Optical Gaming Mouse [Xtrem]
Bus 001 Device 004: ID 214b:7250 Huasheng Electronics USB2.0 HUB
Bus 001 Device 003: ID 214b:7250 Huasheng Electronics USB2.0 HUB
Bus 001 Device 010: ID 05a3:9230 ARC International Camera
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

其他工具可正常捕获图像 #

使用fswebcam捕获图像时一切正常，执行命令：

fswebcam -r 1280x720 --no-banner test.jpg

输出结果：

--- Opening /dev/video0...
Trying source module v4l2...
/dev/video0 opened.
No input was specified, using the first.
--- Capturing frame...
Captured frame in 0.00 seconds.
--- Processing captured image...
Disabling banner.
Writing JPEG image to 'test.jpg'.

OpenCV捕获图像时的异常情况 #

尝试用OpenCV捕获图像时出现异常，两种方式均失败：

方式一：指定/dev/videox路径 #

>>> import cv2
>>>
>>> cam = cv2.VideoCapture('/dev/video0')
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (1824) handleMessage OpenCV | GStreamer warning: Embedded video playback halted; module source reported: Could not read from resource.
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (914) open OpenCV | GStreamer warning: unable to start pipeline
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (501) isPipelinePlaying OpenCV | GStreamer warning: GStreamer: pipeline have not been created

方式二：使用设备编号 #

>>> import cv2
>>> 
>>> cam = cv2.VideoCapture(0)
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (961) open OpenCV | GStreamer warning: Cannot query video position: status=0, value=-1, duration=-1
>>> 

使用环境 #

• Raspberry Pi 4 Model B Rev 1.5
• Raspbian
• python 3.9.2
• pip 23.2.1
• python3-opencv==4.5.1（通过sudo apt install python3-opencv安装）

备注：无法通过pip安装opencv-python

内容的提问来源于stack exchange，提问作者Igor